I have a 3 week old Easter Egger that seems like it hasn't grown at all. Maybe a little bit due to her feathers coming out. We have 14 other chickens with her 1 other being an Easter egger as well that are all growing at normal rate. Our little chicken seems super healthy she eats and drinks just fine. But she does has a small cough. Sometimes she doesn't cough just opens her mouth back to back. No weekness, sneezing, wheezing, eye or nose discharge, or swelling of the eyes or face. She seems super healthy other than the simple cough and no growth. We are scratching our head snd just curious if anyone has any advice.